Very early KDE 6 release.

plasma/plasmoids/io.gitgud.wackyideas.win7showdesktop/contents/ui/lib/ConfigSpinBox.qml

@@ -0,0 +1,54 @@
+import QtQuick 2.15
+import QtQuick.Controls 2.12
+import QtQuick.Layouts 1.3
+
+import org.kde.plasma.plasmoid
+
+RowLayout {
+	id: configSpinBox
+
+	property string configKey: ''
+	property alias to: spinBox.to
+	property alias from: spinBox.from
+	property alias prefix: spinBox.prefix
+	property alias stepSize: spinBox.stepSize
+	property alias suffix: spinBox.suffix
+	property alias value: spinBox.value
+
+	property alias before: labelBefore.text
+	property alias after: labelAfter.text
+
+	Label {
+		id: labelBefore
+		text: ""
+		visible: text
+	}
+
+	SpinBox {
+		id: spinBox
+
+		property string prefix
+		property string suffix
+
+		value: Plasmoid.configuration[configKey]
+		// onValueChanged: Plasmoid.configuration[configKey] = value
+		onValueChanged: serializeTimer.start()
+		to: 2147483647
+
+		textFromValue: function(value) {
+			return prefix + value + suffix;
+		}
+	}
+
+	Label {
+		id: labelAfter
+		text: ""
+		visible: text
+	}
+
+	Timer { // throttle
+		id: serializeTimer
+		interval: 300
+		onTriggered: Plasmoid.configuration[configKey] = value
+	}
+}